This invention relates to an air inlet device of a type for mounting in an opening in the wall of a building for example, in a barn of a type for housing animal husbandry.
The control of air quality within an animal husbandry barn is of extreme importance since the animals produce high levels of humidity and toxic fumes which must be controlled within the barn. In addition, in geographical locations where there are very cold outside temperatures during winter, it is also necessary to ensure that the above fumes and humidity is controlled without excessive loss of heat from the building to reduce to a minimum the application of additional heat to keep the animals at a required temperature.
In many cases air flow into the barn is controlled by a number of inlets which open automatically when the air pressure within the barn drops below a certain amount so as to allow air to flow into the barn through the inlet to replace air pumped out of the barn, for example, by heat exchangers or by exhaust fans. The inlet should of course be able to close to halt the air flow when no additional air is required in the barn so as to control the cold inlet air to the minimum required to keep the barn pressure at the normal operating level.
Generally in a device of this type it is arranged that it can be simply mounted in an opening cut in the wall of the building and attached to the wall to hold the inlet in place. Devices manufactured from a plastics material are much to be preferred in view of the reduced corrosion. In addition, the presentation of the outside inlet opening in an under surface of the device reduces the amount of wind effect on the inlet and also prevents the collection of rain or snow within the inlet.
It is one object of the present invention to provide a particularly advantageous design of inlet of the above general type which satisfies the above requirements and provides an effective device at low manufacturing cost.
According to the invention there is provided an air inlet for mounting in a wall of a building comprising an integrally moulded plastics body defining a sleeve portion of rectangular cross-section having an upper wall, a lower wall and two side walls, one end of the sleeve portion defining a planar open mouth lying in a plane at right angle to the length of the sleeve portion, a hooded inlet portion connected to an opposed end of the sleeve portion and having an upper cover surface extending through an angle of the order of 90 degrees, two sides and a lower open inlet surface arranged at right angles to said open mouth and covered by said sides and said cover surface, an abutment surface at said one end of the sleeve portion extending outwardly therefrom for engaging an inner surface of the wall with the sleeve portion extending through an opening in the wall, a door support flange extending outwardly from said sleeve portion at said open mouth, a door hingedly mounted on said door support flange for movement between a closed position closing said open mouth and an open position exposing said open mouth for passage of air through said inlet, air leakage sealing means coacting between said door and said sleeve portion at said open mouth in said closed position of the door, a pivotal shutter mounted within said sleeve portion comprising a planar rigid rectangular sheet member having a lower edge arranged adjacent one side of said inlet surface and inclined upwardly and longitudinally of said sleeve portion to an upper edge thereof adjacent said open mouth, means mounting said shutter for pivotal movement about said lower edge from the closed position extending across said sleeve portion to prevent the flow of air through said sleeve portion to an open position in which said shutter lies substantially flat along said lower wall of the sleeve portion, and spring means applying a biassing force to said shutter to maintain it in said closed position, each of said upper, lower and side walls of said sleeve portion having at said open mouth integrally moulded therewith a first outwardly extending flange wall and a recess wall generally parallel to the respective wall of the sleeve portion to define a recess surrounding the open mouth, an outer surface of said flange wall defining said abutment surface, an inner surface of said door having extending therefrom a sealing member arrangement to cooperate with an inner surface of said recess wall to define said air leakage ceiling means.
According to a second aspect of the invention an air inlet for mounting in a wall of a building comprising an integrally moulded plastics body defining a sleeve portion of rectangular cross-section having an upper wall, a lower wall and two side walls, one end of the sleeve portion defining a planar open mouth lying in a plane at right angle to the length of the sleeve portion, a hooded inlet portion connected to an opposed end of the sleeve portion and having an upper cover surface extending through an angle of the order of 90 degrees, two sides and a lower open inlet surface arranged at right angles to said open mouth and covered by said sides and said cover surface, an abutment surface at said one end of the sleeve portion extending outwardly therefrom for engaging an inner surface of the wall with the sleeve portion extending through an opening in the wall, a door support flange extending outwardly from said sleeve portion at said open mouth, a door hingedly mounted on said door support flange for movement between a closed position closing said open mouth and an open position exposing said open mouth for passage of air through said inlet, air leakage sealing means coacting between said door and said sleeve portion at said open mouth in said closed position of the door, a pivotal shutter mounted within said sleeve portion comprising a planar rigid rectangular sheet member having a lower edge arranged adjacent one side of said inlet surface and inclined upwardly and longitudinally of said sleeve portion to an upper edge thereof adjacent said open mouth, means mounting said shutter for pivotal movement about said lower edge from the closed position extending across said sleeve portion to prevent the flow of air through said sleeve portion to an open position in which said shutter lies substantially flat along said lower wall of the sleeve portion, and spring means applying a biassing force to said shutter to maintain it in said closed position, said shutter being loosely pivotally mounted within said sleeve portion, said sleeve portion defining a support member for said lower edge of said shutter at a position arranged above the lower wall of said sleeve portion and defining a v-shaped area within which said lower edge is constrained for free pivotal movement.
With the foregoing in view, and other advantages as will become apparent to those skilled in the art to which this invention relates as this specification proceeds, the invention is herein described by reference to the accompanying drawings forming a part hereof, which includes a description of the best mode known to the applicant and of the preferred typical embodiment of the principles of the present invention, in which: